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Abstract:

A composition for a light emitting body-polymer composite, the composition
including a light emitting body; and a cross-linkable composition
including a monomer represented by Chemical Formula 1.
##STR00001##
A light emitting body-polymer composite prepared by cross-linking the
composition and a light emitting device including the light emitting
body-polymer composite are also provided.

Claims:

1. A composition for a light emitting body-polymer composite, the
composition comprising:a light emitting body, anda cross-linkable
composition comprising a monomer represented by the following Chemical
Formula 1: ##STR00017## wherein Ar1 is a substituted or
unsubstituted C6 to C20 arylene, and R1 to R4 are
independently selected from the group consisting of hydrogen, a
substituted or unsubstituted C1 to C20 alkyl, a C3 to
C20 cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to
C16 alkynyl, a substituted or unsubstituted C6 to C20
aryl, a substituted or unsubstituted C1 to C20 alkoxy, a
C7 to C13 arylalkyl, a C1 to C4 oxyalkyl, a C1
to C20 heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro,
a cyano, an amino, an azido, an amidino, a hydrazino, a hydrazono, a
carbonyl, a carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a
sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof.

2. The composition of claim 1, wherein the monomer represented by Chemical
Formula 1 comprises the monomer represented by the following Chemical
Formula 1A: ##STR00018## wherein R1 to R4 are the same as
defined in Chemical Formula 1, and Ra to Rd are independently
selected from the group consisting of hydrogen, a substituted or
unsubstituted C1 to C20 alkyl, a halogen-containing group, a
hydroxyl, and a combination thereof.

3. The composition of claim 2, wherein the monomer represented by Chemical
Formula 1A comprises a monomer represented by the following Chemical
Formula 1AA: ##STR00019## or a combination thereof, wherein R1 to
R4 are the same as defined in the Chemical Formula 1.

4. The composition of claim 1, wherein the cross-linkable composition
further comprises the monomer represented by the following Chemical
Formula 2: ##STR00020## wherein R5 to R8 are independently
selected from the group consisting of hydrogen, a substituted or
unsubstituted C1 to C20 alkyl, a C3 to C20
cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to C16
alkynyl, a substituted or unsubstituted C6 to C20 aryl, a
substituted or unsubstituted C1 to C20 alkoxy, a C7 to
C13 arylalkyl, a C1 to C4 oxyalkyl, a C1 to C20
heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro, a cyano, an
amino, an azido, an amidino, a hydrazino, a hydrazono, a carbonyl, a
carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a sulfonic
acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof, provided that at
least one of R7 and R8 is a C1 to C20 alkyl.

5. The composition of claim 4, wherein the monomer represented by Chemical
Formula 1 and the monomer represented by Chemical Formula 2 are included
in an amount of about 5 to about 70 volume percent and about 30 to about
95 volume percent, respectively, based on the total amount of the
cross-linkable composition.

6. The composition of claim 1, wherein the cross-linkable composition
further comprises at least one of a monomer represented by the following
Chemical Formula 3 and a monomer including at least two (meth)acrylate
groups: ##STR00021## wherein Ar2 is a substituted or unsubstituted
C6 to C20 aryl, and R9 and R10 are independently
selected from the group consisting of hydrogen, a substituted or
unsubstituted C1 to C20 alkyl, a C3 to C20
cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to C16
alkynyl, a substituted or unsubstituted C6 to C20 aryl, a
substituted or unsubstituted C1 to C20 alkoxy, a C7 to
C13 arylalkyl, a C1 to C4 oxyalkyl, a C1 to C20
heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro, a cyano, an
amino, an azido, an amidino, a hydrazino, a hydrazono, a carbonyl, a
carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a sulfonic
acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof.

7. The composition of claim 6, wherein the monomer represented by Chemical
Formula 3 comprises the monomer represented by the following Chemical
Formula 3A: ##STR00022## wherein in Chemical Formula 3A, R9 and
R10 are the same as defined in the Chemical Formula 3, and Re
to Ri are independently selected from the group consisting of
hydrogen, a substituted or unsubstituted C1 to C20 alkyl, a
halogen-containing group, a hydroxyl, and a combination thereof.

8. The composition of claim 6, wherein the monomer represented by Chemical
Formula 3 is included in an amount of about 2 to about 50 volume percent,
based on the total amount of the cross-linkable composition.

9. The composition of claim 6, wherein the monomer including at least two
(meth)acrylate groups comprises a monomer represented by the following
Chemical Formula 4: ##STR00023## wherein R11 to R16 are
independently selected from the group consisting of hydrogen, a
substituted or unsubstituted C1 to C20 alkyl, a C3 to
C20 cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to
C16 alkynyl, a substituted or unsubstituted C6 to C20
aryl, a substituted or unsubstituted C1 to C20 alkoxy, a
C7 to C13 arylalkyl, a C1 to C4 oxyalkyl, a C1
to C20 heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro,
a cyano, an amino, an azido, an amidino, a hydrazino, a hydrazono, a
carbonyl, a carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a
sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and combinations thereof, and R17 is
selected from the group consisting of a substituted or unsubstituted
C1 to C20 alkylene, a substituted or unsubstituted C3 to
C20 cycloalkylene, a substituted or unsubstituted C6 to
C20 arylene, a substituted or unsubstituted C2 to C20
heteroarylene, and a combination thereof.

10. The composition of claim 6, wherein the monomer including at least two
(meth)acrylate groups is included in an amount of about 2 to about 50
volume percent, based on the total amount of the cross-linkable
composition.

12. The light emitting body-polymer composite of claim 11, wherein the
cross-linked composition has a refractive index of about 1.4 to about
1.6.

13. A light emitting device, comprising:a light emitting body-polymer
composite including a light emitting body and a cross-linked
resin,wherein the cross-linked resin comprises a polymerization product
of the monomer represented by Chemical Formula 1: ##STR00024## wherein
Ar1 is a substituted or unsubstituted C6 to C20 arylene,
and R1 to R4 are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a C3 to C20 cycloalkyl, a C1 to C20
heterocycloalkyl, a C2 to C16 alkynyl, a substituted or
unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof.

14. The light emitting device of claim 13, wherein the cross-linked resin
comprises a polymerization product of a monomer represented by the
following Chemical Formula 2: ##STR00025## wherein R5 to R8 are
independently selected from the group consisting of hydrogen, a
substituted or unsubstituted C1 to C20 alkyl, a C3 to
C20 cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to
C16 alkynyl, a substituted or unsubstituted C6 to C20
aryl, a substituted or unsubstituted C1 to C20 alkoxy, a
C7 to C13 arylalkyl, a C1 to C4 oxyalkyl, a C1
to C20 heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro,
a cyano, an amino, an azido, an amidino, a hydrazino, a hydrazono, a
carbonyl, a carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a
sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof, provided that at
least one of R7 and R8 is a C1 to C20 alkyl.

15. The light emitting device of claim 13, wherein the cross-linked resin
comprises at least one of a polymerization product of a monomer
represented by Chemical Formula 3 and a polymerization product of a
monomer including a least two (meth)acrylate groups: ##STR00026## wherein
Ar2 is a substituted or unsubstituted C6 to C20 aryl, and
R9 and R10 are independently selected from the group consisting
of hydrogen, a substituted or unsubstituted C1 to C20 alkyl, a
C3 to C20 cycloalkyl, a C1 to C20 heterocycloalkyl, a
C2 to C16 alkynyl, a substituted or unsubstituted C6 to
C20 aryl, a substituted or unsubstituted C1 to C20 alkoxy,
a C7 to C13 arylalkyl, a C1 to C4 oxyalkyl, a C1
to C20 heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro,
a cyano, an amino, an azido, an amidino, a hydrazino, a hydrazono, a
carbonyl, a carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a
sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof.

17. The light emitting device of claim 16, wherein light emitting diode
and the light emitting body emit light,the light emitting body emits
light having a wavelength which is longer than a wavelength the light
emitted from the light emitting diode, andthe combination of the light
emitting diode and the light emitting body emit white light.

18. The light emitting device of claim 13, wherein the light emitting
device further comprises a first electrode disposed on a first side of
the light emitting body-polymer composite, and a second electrode
disposed on a second side the light emitting body-polymer composite,
wherein the first side is opposite the second side.

21. The light emitting device of claim 20, wherein the polymer resin
comprises an epoxy resin, a silicone resin, or a combination thereof.

Description:

CROSS-REFERENCE TO RELATED APPLICATION

[0001]This application claims priority to Korean Patent Application No.
10-2009-0062752, filed on Jul. 9, 2009, all the benefits accruing
therefrom under 35 U.S.C. §119, the content of which in its entirety
is herein incorporated by reference.

BACKGROUND

[0002]1. Field

[0003]This disclosure relates to a composition for a light emitting
body-polymer composite, a light emitting body-polymer composite, and a
light emitting device including the same.

[0004]2. Description of the Related Art

[0005]A light emitting device, such as a light emitting diode ("LED"), an
organic light emitting device ("OLED"), or a photoluminescent ("PL")
device, is applicable to various types of devices, including electric
home appliances, lighting devices, display devices, and automation
devices.

[0006]The light emitting device, which includes a light emitting body, may
express an original color of a light emitting material, such as blue,
red, or green, and the light emitting device may express white by
emitting a plurality of colors from a plurality of light emitting
materials, which express different colors.

[0007]The light emitting device may be generally fabricated in a packaging
material or within an encapsulating structure.

[0008]The packaging material or encapsulating structure includes a
transparent resin capable of passing light emitted from a light emitting
body to the outside, and desirably prevents external moisture or oxygen
from contacting the device. However, the transparent resin may not
prevent the inflow of external moisture or oxygen, and the moisture or
oxygen may deteriorate the light emitting body and shorten the life-span
of the light emitting body, degrading the performance of the light
emitting device. Therefore there remains a need for an improved
transparent material for a light emitting body of a light emitting
device.

SUMMARY

[0009]A feature, advantage, or aspect of this disclosure is a composition
for a light emitting body-polymer composite, which prevents the inflow of
moisture and oxygen from the outside and provides high transparency and
an improved the life-span of a light emitting device.

[0010]Another aspect, feature, or advantage of this disclosure is a light
emitting body-polymer composite formed by cross-linking a composition for
a light emitting body-polymer composite.

[0011]Yet another aspect, feature, or advantage of this disclosure is a
light emitting device including the light emitting body-polymer
composite.

[0012]Disclosed is a composition for a light emitting body-polymer
composite, the composition including a light emitting body; and a
cross-linkable composition includina a monomer represented by the
following Chemical Formula 1:

##STR00002##

wherein Ar1 is a substituted or unsubstituted C6 to C20
arylene, and R1 to R4 are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a C3 to C20 cycloalkyl, a C1 to C20
heterocycloalkyl, a C2 to C16 alkynyl, a substituted or
unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof.

[0013]The monomer represented by Chemical Formula 1 may include the
monomer represented by the following Chemical Formula 1A:

##STR00003##

wherein R1 to R4 are the same as defined in the Chemical Formula
1, and Ra to Rd are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a halogen-containing group, a hydroxyl, and a combination
thereof.

[0014]The monomer represented by Chemical Formula 1A may include the
monomer represented by the following Chemical Formula 1AA:

##STR00004##

or a combination thereof, wherein R1 to R4 are the same as
defined in Chemical Formula 1.

[0015]The cross-linkable composition may further include the monomer
represented by the following Chemical Formula 2:

##STR00005##

wherein R6 to R8 are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a C3 to C20 cycloalkyl, a C1 to C20
heterocycloalkyl, a C2 to C16 alkynyl, a substituted or
unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof, provided that at least one of R7 and R8 is
a C1 to C20 alkyl.

[0016]The monomer represented by Chemical Formula 1 and the monomer
represented by Chemical Formula 2 may be included in an amount of about 5
to about 70 volume percent ("%") and about 30 to about 95 volume %,
respectively, based on the total amount of the cross-linkable
composition.

[0017]The cross-linkable composition may further include at least one of a
monomer represented by the following Chemical Formula 3 and a monomer
including at least two (meth)acrylate groups:

##STR00006##

wherein Ar2 is a substituted or unsubstituted C6 to C20
aryl, and R9 and R10 are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a C3 to C20 cycloalkyl, a C1 to C20
heterocycloalkyl, a C2 to C16 alkynyl, a substituted or
unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof.

[0018]The monomer represented by Chemical Formula 3 includes the monomer
represented by the following Chemical Formula 3A:

##STR00007##

wherein R9 and R10 are the same as defined in Chemical Formula
3, and Re to Ri are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a halogen-containing group, a hydroxyl, and a combination
thereof.

[0019]The monomer represented by Chemical Formula 3 may be included in an
amount of about 2 to about 50 volume %, based on the total amount of the
cross-linkable composition.

[0020]The monomer including at least two (meth)acrylate groups may include
a monomer represented by Chemical Formula 4:

##STR00008##

wherein R11 to R16 are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a C3 to C20 cycloalkyl, a C1 to C20
heterocycloalkyl, a C2 to C16 alkynyl, a substituted or
unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof, and R17 is selected from the group consisting
of a substituted or unsubstituted C1 to C20 alkylene, a
substituted or unsubstituted C3 to C20 cycloalkylene, a
substituted or unsubstituted C6 to C20 arylene, a substituted
or unsubstituted C2 to C20 heteroarylene, and a combination
thereof.

[0021]The monomer including at least two (meth)acrylate groups may be
included in an amount of about 2 to about 50 volume %, based on the total
amount of the cross-linkable composition.

[0022]According to another aspect, feature, or advantage of this
disclosure, a light emitting body-polymer composite may be prepared by
cross-linking the composition for the light emitting body-polymer
composite.

[0023]In an embodiment, the cross-linked composition has a refractive
index of about 1.4 to about 1.6.

[0024]Also disclosed is a light emitting device, including: a light
emitting body-polymer composite including a light emitting body and a
cross-linked resin, wherein the cross-linked resin includes a
polymerization product of the monomer represented by the Chemical Formula
1:

##STR00009##

wherein Ar1 is a substituted or unsubstituted C6 to C20
arylene, and R1 to R4 are independently selected from the group
consisting of hydrogen, a substituted or unsubstituted C1 to
C20 alkyl, a C3 to C20 cycloalkyl, a C1 to C20
heterocycloalkyl, a C2 to C16 alkynyl, a substituted or
unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof.

[0025]The cross-linked resin may further include a polymerization product
of a monomer represented by the Chemical Formula 2.

[0026]The cross-linked resin may further include at least one of a
polymerization product of a monomer represented by Chemical Formula 3 and
a polymerization product of a monomer including a least two
(meth)acrylate groups.

[0027]The light emitting device may further include a light emitting diode
that provides the light emitting body-polymer composite with light.

[0028]The light emitting diode and the light emitting body may emit light,
the light emitting body may emit light having a wavelength which is
longer than a wavelength of the light emitted from the light emitting
diode, and the combination of the light emitting diode and the light
emitting body emit white light.

[0029]The light emitting device may further include a first electrode
disposed on a first side of the light emitting body-polymer composite,
and a second electrode disposed on a second side of the light emitting
body-polymer composite, wherein the first side is opposite the second
side.

[0030]The light emitting body-polymer composite may have a spherical
shape.

[0031]The light emitting device may further include a polymer resin
surrounding the light emitting body-polymer composite, and the polymer
resin may include an epoxy resin, a silicone resin, or a combination
thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032]The above and other aspects, advantages and features of this
disclosure will become more apparent by describing in further detail
exemplary embodiments thereof with reference to the accompanying
drawings, in which:

[0033]FIG. 1 is a schematic view showing an exemplary embodiment of a
light emitting device;

[0034]FIG. 2 is a schematic view showing an exemplary embodiment of
another light emitting device;

[0035]FIG. 3 is a cross-sectional view showing an exemplary embodiment of
another light emitting device;

[0036]FIG. 4 is a graph illustrating luminance (lumens per watt, Im/W)
versus time (days) of the light emitting devices according to Examples 1
and 2;

[0037]FIG. 5 is a graph illustrating power conversion efficiency (percent)
versus time (days) of the light emitting devices according to Examples 1
and 2;

[0038]FIG. 6 is a graph illustrating luminance (lumens per watt) versus
time (days) of the light emitting device according to Comparative Example
1;

[0039]FIG. 7 is a graph illustrating power conversion efficiency (percent)
versus time (days) of the light emitting device according to Comparative
Example 1; and

[0040]FIG. 8 is a graph illustrating luminance (lumens per watt) versus
time (days) of the light emitting device according to Examples 3 to 8 and
Comparative Examples 2 and 3.

DETAILED DESCRIPTION

[0041]Exemplary embodiments will be described more fully hereinafter with
reference to the accompanying drawings. The present invention may,
however, be embodied in many different forms and should not be construed
as limited to the exemplary embodiments set forth herein.

[0042]As used herein, unless otherwise provided, the term "substituted"
refers to a compound or group substituted with one selected from the
group consisting of a halogen, such as F, Cl, Br, and I, a hydroxy, an
alkoxy, a nitro, a cyano, an amino, an azido, an amidino, a hydrazino, a
hydrazono, a carbonyl, a carbamyl, a thiol, an ester, a carboxyl or a
salt thereof, a sulfonic acid or a salt thereof, a phosphoric acid or a
salt thereof, a C1 to C20 alkyl, a C2 to C16 alkynyl,
a C6 to C20 aryl, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a C3 to C20 cycloalkyl, a C3 to
C15 cycloalkenyl, a C6 to C15 cycloalkynyl, a
heterocycloalkyl, and combinations thereof, instead of at least one
hydrogen of the designated compound or group.

[0043]As used herein, unless otherwise provided, the term, "hetero" refers
to a compound or group including 1 to 3 heteroatoms selected from the
group consisting of N, O, S, and P, and a combination thereof.

[0044]It will be understood that, although the terms first, second, third
etc. may be used herein to describe various elements, components,
regions, layers, and/or sections, these elements, components, regions,
layers, and/or sections should not be limited by these terms. These terms
are only used to distinguish one element, component, region, layer, or
section from another element, component, region, layer, or section. Thus,
a first element, component, region, layer, or section discussed below
could be termed a second element, component, region, layer, or section
without departing from the teachings of the present invention.

[0045]The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting. As used
herein, the terms "a" and "an" are open terms that may be used in
conjunction with singular items or with plural items. Thus as used
herein, the singular forms "a," "an," and "the" are intended to include
the plural forms as well, unless the context clearly indicates otherwise.
It will be further understood that the terms "comprises" and/or
"comprising," or "includes" and/or "including" when used in this
specification, specify the presence of stated features, regions,
integers, steps, operations, elements, and/or components, but do not
preclude the presence or addition of one or more other features, regions,
integers, steps, operations, elements, components, and/or groups thereof.

[0046]Furthermore, relative terms, such as "lower" or "bottom" and "upper"
or "top," may be used herein to describe one element's relationship to
another element as illustrated in the Figures. It will be understood that
relative terms are intended to encompass different orientations of the
device in addition to the orientation depicted in the Figures. For
example, if the device in one of the figures is turned over, elements
described as being on the "lower" side of other elements would then be
oriented on "upper" sides of the other elements. The exemplary term
"lower," can therefore, encompasses both an orientation of "lower" and
"upper," depending on the particular orientation of the figure.
Similarly, if the device in one of the figures is turned over, elements
described as "below" or "beneath" other elements would then be oriented
"above" the other elements. The exemplary terms "below" or "beneath" can,
therefore, encompass both an orientation of above and below.

[0047]Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this invention
belongs.

[0048]Exemplary embodiments are described herein with reference to cross
section illustrations that are schematic illustrations of idealized
embodiments. As such, variations from the shapes of the illustrations as
a result, for example, of manufacturing techniques and/or tolerances, are
to be expected. Thus, embodiments described herein should not be
construed as limited to the particular shapes of regions as illustrated
herein but are to include deviations in shapes that result, for example,
from manufacturing. For example, a region illustrated or described as
flat may, typically, have rough and/or nonlinear features. Moreover,
sharp angles that are illustrated may be rounded. Thus, the regions
illustrated in the figures are schematic in nature and their shapes are
not intended to illustrate the precise shape of a region and are not
intended to limit the scope of the present claims.

[0049]As used herein, the term "(meth)acrylate" refers to both acrylate
and methacrylate.

[0050]In the drawings, the thickness of layers, films, panels, regions,
etc., are exaggerated for clarity. Like reference numerals designate like
elements throughout the specification. It will be understood that when an
element such as a layer, film, region, or substrate is referred to as
being "on" another element, it can be directly on the other element or
intervening elements may also be present. In contrast, when an element is
referred to as being "directly on" another element, there are no
intervening elements present.

[0051]As used herein, the term "and/or" includes any and all combinations
of one or more of the associated listed items.

[0052]Hereinafter, an exemplary embodiment of the light emitting device is
described with reference to FIG. 1. FIG. 1 is a schematic view showing an
exemplary embodiment of a light emitting device.

[0053]Referring to FIG. 1, the light emitting device according to an
embodiment includes a light source 120, a medium layer 125 disposed on
the light source 120, and a transparent resin layer 130 disposed on the
medium layer 125.

[0054]The light source 120 supplies light to the transparent resin layer
130 and may include a light emitting diode ("LED"). The light emitting
diode may comprise an inorganic semiconductor material and include, for
example, an InGaN compound, an AlGaN compound, an InGaAlN compound, or a
combination thereof. The light emitting diode may be connected to a lead
frame (not shown), which is electrically connected with an external power
source, and emits visible light having a certain color when electric
power is applied. The light emitting diode may include, for example, a
blue light emitting diode, which emits blue light.

[0055]The medium layer 125 is a medium (e.g., material), which is capable
of passing the light supplied from the light source 120 to the
transparent resin layer 130, and comprises, for example, air, vacuum, a
transparent resin, a liquid crystal, or a combination thereof. The medium
layer 125 physically separates the light source 120 and the transparent
resin layer 130, and it may be omitted.

[0056]The transparent resin layer 130 includes a light emitting
body-polymer composite 140 having a spherical shape and a polymer resin
150 surrounding the light emitting body-polymer composite 140. The
polymer resin 150 may be on a surface of the light emitting body-polymer
composite 140 and may comprise a polymer.

[0058]The light emitting body 141 includes a photoluminescent material,
which emits light upon excitation by light, and may include, for example,
a phosphor, a quantum dot such as a semiconductor nanocrystal, or a
combination thereof. The phosphor may include, for example, a blue
phosphor, a green phosphor, a red phosphor, or a combination thereof.

[0059]The blue phosphor, for example, may include at least one phosphor
selected from (Sr,Ba,Ca)5(PO4)3Cl:Eu2+;
BaMg2Al16O27:Eu2+;
Sr4Al14O25:Eu2+; BaAl8O13:Eu2+;
BaMgAl10O17:Eu2+ and
Sr2Si3O8.2SrCl2:Eu2+;
Ba3MgSi2O8:Eu2+; or
(Sr,Ca)10(PO4)6.nB2O3:Eu2+ (n=1-30), or the
like.

[0060]The green phosphor, for example, may include at least one phosphor
selected from (Ba,Sr,Ca)2SiO4:Eu2+;
Ba2MgSi2O7:Eu2+; Ba2ZnSi2O7:Eu2+;
BaAl2O4:Eu2+; SrAl2O4:Eu2+;
BaMgAl10O17:Eu2+, Mn2+; or
BaMg2Al16O27:Eu2+, Mn2+, or the like.

[0061]The red phosphor, for example, may include at least one phosphor
selected from (Ba,Sr,Ca)2Si5N8:Eu2+;
(Sr,Ca)AlSiN3:Eu2+; Y2O3:Eu3+,Bi3+;
(Ca,Sr)S:Eu2+; CaLa2S4:Ce3+;
(Sr,Ca,Ba)2P2O7:Eu2+,Mn2+;
(Ca,Sr)10(PO4)6(F,Cl):Eu2+,Mn2+;
(Y,Lu)2WO6:Eu3+,Mo6+;
(Gd,Y,Lu,La)2O3:Eu3+,Bi3+;
(Gd,Y,Lu,La)2O2S:Eu3+,Bi3+;
(Gd,Y,Lu,La)BO3:Eu3+,Bi3+;
(Gd,Y,Lu,La)(P,V)O4:Eu3+,Bi3+; or
(Ba,Sr,Ca)MgP2O7:Eu2+,Mn2+, or the like.

[0062]The semiconductor nanocrystal is not specifically limited, and may
be selected from the group consisting of a Group II-VI semiconductor
compound, a Group II-V semiconductor compound, a Group III-VI
semiconductor compound, a Group III-V semiconductor compound, a Group
IV-VI semiconductor compound, a Group II-III-VI compound, a Group
II-IV-VI compound, a Group II-IV-V compound, alloys thereof, and a
combination thereof, wherein the Groups II, III, IV, V and VI, for
example, refer to groups of the periodic table of the elements.

[0063]The Group II element may include, for example, Zn, Cd, Hg, or a
combination thereof; the Group III element may include, for example, Al,
Ga, In, Ti, or a combination thereof; and the Group IV element may
include, for example, Si, Ge, Sn, Pb, or a combination thereof. The Group
V element may include, for example, P, As, Sb, Bi, or a combination
thereof; and the Group VI element may include, for example, O, S, Se, Te,
or a combination thereof.

[0064]The Group II-VI semiconductor compound may be selected from the
group consisting of, for example, a binary element compound such as CdS,
CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, and the like; a
ternary element compound such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe,
ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe,
CdHgTe, HgZnS, HgZnSe, and the like; and a quaternary element compound
such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS,
HgZnSeTe, HgZnSTe, and the like, and a combination thereof. In addition,
the Group III-V semiconductor compound may be selected from the group
consisting of, for example, a binary element compound such as GaN, GaP,
GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and the like; a
ternary element compound such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP,
AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP,
AlGaN, AlGaP, AlGaAs, AlGaSb, InGaN, InGaP, InGaAs, InGaSb, AlInN, AlInP,
AlinAs, AlInSb, and the like; and a quaternary element compound such as
GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GalnPAs,
GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and the like, and a
combination thereof. The Group IV-VI compound may be selected from the
group consisting of, for example, a binary element compound such as SnS,
SnSe, SnTe, PbS, PbSe, PbTe, and the like; a ternary element compound
such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe,
SnPbTe, and the like; or a quaternary element compound such as SnPbSSe,
SnPbSeTe, SnPbSTe, and the like, and a combination thereof.

[0065]The semiconductor nanocrystal may have a core-shell structure. The
shell may include a least one layer and includes, for example, a Group
II-VI semiconductor, a Group III-V semiconductor, a Group IV-VI
semiconductor, or a combination thereof.

[0066]The semiconductor nanocrystal may comprise a multi-layered structure
consisting of two or more kinds of materials. The semiconductor
nanocrystal having a multi-layered structure may include an alloy
interlayer including at least two kinds of materials in interposed
between layers, and the alloy interlayer may be an alloy layer having a
gradient of a material composition.

[0067]In addition, the semiconductor nanocrystal may have a surface capped
with an organic ligand. The organic ligand may include, for example, a
thiol, an amine, a phosphine, a carboxylic acid, or the like, or a
combination thereof. The organic ligand may include a C6 to C24
alkane or alkene having a --COOH terminal end group; a C6 to
C24 alkane or alkene having a --PO3H2 terminal end group;
a C6 to C24 alkane or alkene having a --PO terminal end group;
a C6 to C24 alkane or alkene having a --SH terminal end group;
a C6 to C24 alkane or alkene having a --NH2 terminal end
group, or a combination thereof. In addition, the organic ligand may
include oleic acid, stearic acid, palmitic acid, hexyl phosphonic acid,
n-octyl phosphonic acid, tetradecyl phosphonic acid, octadecyl phosphonic
acid, trioctylphosphine oxide, n-octyl amine, hexadecyl amine,
trioctylamine, or a combination thereof.

[0068]The light emitting body 141 may include a first light emitting body
141a and a second light emitting body 141b, which emit different colors
than each other, and emit light of a wavelength intrinsic to the light
emitting body by using light supplied from a light emitting diode of the
light source 120. The light emitting body 141 emits light having a
wavelength which is longer than a wavelength of the light supplied from
the light emitting diode. For example, when the light source 120 includes
a blue light emitting diode, the first light emitting body 141a may emit
red light and the second light emitting body 141b may emit green light.
However, the light emitting device is not limited thereto, and the kind
of light emitting body 141 and the color of the emitted light may be
varied.

[0069]The light emitted from the light emitting diode, the light emitted
from the first light emitting body 141a, and the light emitted from the
second light emitting body 141b may, in combination, make white light.
For better understanding, clarity, and ease of description, two kinds of
light emitting bodies 141a and 141b are disclosed, although the light
emitting device is not limited thereto. The light emitting device may
include a plurality of various kinds of light emitting bodies as long as
it expresses white light in combination with the light emitted from the
light emitting diode when on.

[0070]The cross-linkable resin 142 may be formed by polymerizing a
cross-linkable composition including a monomer, which is capable of
cross-linking.

[0071]The cross-linkable composition includes a monomer represented by the
following Chemical Formula 1.

##STR00010##

[0072]In Chemical Formula 1, Ar1 is a substituted or unsubstituted
C6 to C20 arylene, and R1 to R4 are independently
selected from the group consisting of hydrogen, a substituted or
unsubstituted C1 to C20 alkyl, a C3 to C20
cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to C16
alkynyl, a substituted or unsubstituted C6 to C20 aryl, a
substituted or unsubstituted C1 to C20 alkoxy, a C7 to
C13 arylalkyl, a C1 to C4 oxyalkyl, a C1 to C20
heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro, a cyano, an
amino, an azido, an amidino, a hydrazino, a hydrazono, a carbonyl, a
carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a sulfonic
acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof.

[0073]Because the monomer represented by Chemical Formula 1 has two vinyl
groups, it may be cross-linked. Thereby, the cross-linked polymerization
product may have a dense and rigid structure. In addition, when at least
one of R1 to R4 is substituted with a substituent having a
binding site, the cross-linked polymerization product may have a denser
and more rigid structure because the number of binding sites in the
cross-linkable composition which are capable of cross-linking are
increased.

[0074]Furthermore, because the monomer represented by Chemical Formula 1
has a water-repellent property, it may reduce or effectively prevent the
inflow of moisture from the outside.

[0075]The monomer represented by Chemical Formula 1 may include a monomer
represented by the following Chemical Formula 1A.

##STR00011##

[0076]In the Chemical Formula 1A, R1 to R4 are the same as
defined in Chemical Formula 1, and Ra to Rd are independently
selected from the group consisting of hydrogen, a substituted or
unsubstituted C1 to C20 alkyl, a halogen-containing group, a
hydroxyl, and a combination thereof.

[0077]The monomer represented by Chemical Formula 1A may be divinyl
benzene in which each of R1 to R4 and Ra to Rd is
hydrogen.

[0078]In addition, the monomer represented by Chemical Formula 1A may
include at least one monomer selected from the group consisting of the
following Chemical Formula 1AA:

##STR00012##

and a combination thereof.

[0079]In Chemical Formula 1AA, R1 to R4 are the same as defined
in Chemical Formula 1.

[0080]The monomer represented by Chemical Formula 1 may be included in an
amount of about 5 to about 70 volume percent ("%"), specifically about 10
to about 65 volume %, more specifically about 20 to about 55 volume %,
based on the total amount of the cross-linkable composition. When the
monomer is included within the foregoing range, the monomer has a
suitable cross-linking density, which is sufficient to reduce or
effectively prevent moisture inflow from the outside and a reduction in
volume. Thereby, the monomer does not cause the light emitting body to be
phase-separated, so it is possible to provide a uniform light emitting
body-polymer composite.

[0081]The cross-linkable composition may further include a monomer
represented by the following Chemical Formula 2.

##STR00013##

[0082]In Chemical Formula 2, R5 to R8 are independently selected
from the group consisting of hydrogen, a substituted or unsubstituted
C1 to C20 alkyl, a C3 to C20 cycloalkyl, a C1 to
C20 heterocycloalkyl, a C2 to C16 alkynyl, a substituted
or unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof, provided that at least one of R7 and R8 is
a C1 to C20 alkyl.

[0083]The monomer represented by Chemical Formula 2 may be an alkyl
(meth)acrylate monomer in which each of R5 and R6 is hydrogen
and each of R7 and R8 is a C1 to C20 alkyl group.

[0084]The monomer represented by Chemical Formula 2 may be cross-linked in
the center of the acryl group. In addition, since an alkyl group in the
terminal position has high hydrophobicity, it may reduce or effectively
prevent moisture inflow from the outside and phase separation from the
light emitting body when a polymer composition is formed during
manufacture, for example.

[0085]The monomer represented by Chemical Formula 2 may be included in an
amount of about 30 to about 95 volume %, specifically about 40 to about
85 volume %, more specifically about 50 to about 75 volume %, based on
the total amount of cross-linkable composition. When the monomer of
Chemical Formula 2 is included in the foregoing range, it is believed to
reduce or effectively prevent moisture inflow from outside and phase
separation from the light emitting body by being cross-linked in a dense
structure.

[0086]The cross-linkable composition may further include a monomer
represented by the following Chemical Formula 3.

##STR00014##

[0087]In Chemical Formula 3, Ar2 is a substituted or unsubstituted
C6 to C20 aryl, R9 and R10 are independently selected
from the group consisting of hydrogen, a substituted or unsubstituted
C1 to C20 alkyl, a C3 to C20 cycloalkyl, a C1 to
C20 heterocycloalkyl, a C2 to C16 alkynyl, a substituted
or unsubstituted C6 to C20 aryl, a substituted or unsubstituted
C1 to C20 alkoxy, a C7 to C13 arylalkyl, a C1 to
C4 oxyalkyl, a C1 to C20 heteroalkyl, a C3 to
C20 heteroarylalkyl, a nitro, a cyano, an amino, an azido, an
amidino, a hydrazino, a hydrazono, a carbonyl, a carbamyl, a thiol, an
ester, a carboxyl or a salt thereof, a sulfonic acid or a salt thereof, a
phosphoric acid or a salt thereof, a halogen-containing group, and a
combination thereof.

[0088]The monomer represented by Chemical Formula 3 may be a monomer
represented by the following Chemical Formula 3A.

##STR00015##

[0089]In Chemical Formula 3A, R9 and R10 are the same as defined
in Chemical Formula 3, and Re to Ri are independently selected
from the group consisting of hydrogen, a substituted or unsubstituted
C1 to C20 alkyl, a halogen-containing group, a hydroxyl, and a
combination thereof.

[0090]The monomer represented by Chemical Formula 3A may be a styrene
monomer in which each of R9 and R10 and Re to Ri is
hydrogen.

[0091]The monomer represented by Chemical Formula 3 may be included in an
amount of about 2 to about 50 volume %, specifically about 4 to about 45
volume %, more specifically about 6 to about 40 volume %, based on the
total amount of the cross-linkable composition. When the monomer of
Chemical Formula 3 is included in the range, the light emitting
body-polymer composite may improve a heat resistance and a
hydrophobicity, reducing or effectively preventing thermal distortion by
heat generated from a light source.

[0092]The cross-linkable composition may further include a monomer having
at least two acrylate groups. The monomer having at least two acrylate
groups may include a di(meth)acrylate monomer represented by Chemical
Formula 4.

[0094]In the Chemical Formula 4, R11 to R16 are independently
selected from the group consisting of hydrogen, a substituted or
unsubstituted C1 to C20 alkyl, a C3 to C20
cycloalkyl, a C1 to C20 heterocycloalkyl, a C2 to C16
alkynyl, a substituted or unsubstituted C6 to C20 aryl, a
substituted or unsubstituted C1 to C20 alkoxy, a C7 to
C13 arylalkyl, a C1 to C4 oxyalkyl, a C1 to C20
heteroalkyl, a C3 to C20 heteroarylalkyl, a nitro, a cyano, an
amino, an azido, an amidino, a hydrazino, a hydrazono, a carbonyl, a
carbamyl, a thiol, an ester, a carboxyl or a salt thereof, a sulfonic
acid or a salt thereof, a phosphoric acid or a salt thereof, a
halogen-containing group, and a combination thereof, and R17 is
selected from the group consisting of a substituted or unsubstituted
C1 to C20 alkylene, a substituted or unsubstituted C3 to
C20 cycloalkylene, a substituted or unsubstituted C6 to
C20 arylene, a substituted or unsubstituted C2 to C20
heteroarylene, and a combination thereof.

[0097]The monomer having at least two acrylate groups may be included in
an amount of about 2 to about 50 volume %, specifically about 4 to about
45 volume %, more specifically about 6 to about 40 volume %, based on the
total amount of cross-linkable composition.

[0098]The polymer formed by cross-linking the cross-linkable composition
may have a refractive index of about 1 to about 2, specifically about 1.4
to about 1.6, more specifically about 1.5. When the polymer has the
foregoing refractive index, a light emitting body-polymer composite
absorbs light from a light source, and thereby the light emitting
efficiency may be increased.

[0099]The polymer resin 150 surrounds the light emitting body-polymer
composite 140 and seals (e.g., hermetically seals) a light emitting part
120 and a medium part 125. The polymer resin 150 may be on a surface of
the light emitting body-polymer composite 140.

[0100]The polymer resin 150 may comprise a transparent material, which is
capable of passing the light supplied from the light source 120 and the
light supplied from light emitting body 141, and it may include, for
example, an epoxy resin, a silicone resin, or a combination thereof.

[0101]Hereinafter, a method of fabricating the light emitting device is
further disclosed.

[0103]First, a cross-linkable composition including the monomer is
prepared. Then a polymerization initiator is added to and mixed with the
cross-linkable composition. The polymerization initiator may include, for
example, a thermal polymerization initiator, a photopolymerization
initiator, an ion polymerization initiator, an emulsion polymerization
initiator, a suspension polymerization initiator, or a combination
thereof.

[0104]Subsequently, a light emitting body 141 is mixed with the
cross-linkable composition, and the mixture of the cross-linkable
composition and the light emitting body 141 is polymerized to provide a
light emitting body-polymer composite 140. The polymerization may be
selected from the group consisting of thermal polymerization,
photopolymerization, ion polymerization, suspension polymerization,
emulsion polymerization, or a combination thereof.

[0105]Then the obtained light emitting body-polymer composite 140 is dried
under reduced pressure, and the dried light emitting body-polymer
composite 140 is pulverized to provide a particle having a selected
shape, which may be a spherical shape.

[0106]Subsequently, the light emitting body-polymer composite 140 having a
particle shape is mixed with a resin composition 150, such as an epoxy
resin, a silicone resin, or a combination thereof.

[0107]A mixed solution of the light emitting body-polymer composite 140
and the resin composition 150 is dried under reduced pressure to remove
air and moisture from the mixed solution.

[0108]The mixed solution of the light emitting body-polymer composite 140
and the resin composition 150 is then disposed on a light source 120,
including a light emitting diode, and a medium layer 125, and the mixed
solution is hardened.

[0109]Hereinafter, a light emitting device according to another embodiment
is described with reference to FIG. 2.

[0110]FIG. 2 is a schematic view showing a light emitting device according
to another embodiment.

[0111]Referring to FIG. 2, the light emitting device may include a light
source 120 including a light emitting diode, a medium layer 125, and a
transparent resin layer 130 including a light emitting body-polymer
composite 140 and a polymer resin 150 as in the above embodiment.

[0112]However, differing from the above embodiment, each light emitting
body-polymer composite 140 includes a single type of light emitting body
141, which emits light of a single selected color. In other words, each
light emitting body-polymer composite 140, which may have a spherical
shape, may include a first light emitting body 141a, and another light
emitting body-polymer composite 140 includes a second light emitting body
141b, and wherein, in an embodiment, the first light emitting body and
the second light emitting body are different and emit light of a
different wavelength.

[0113]In an embodiment, white light is expressed by a combination of light
emitted from the light emitting diode, light emitted from the first light
emitting body 141a, and light emitted from the second light emitting body
141b. For better understanding, clarity, and ease of description, only
two kinds of light emitting bodies 141a and 141b are disclosed in the
foregoing description, but the light emitting device is not limited
thereto. The light emitting device may include various kinds of light
emitting bodies.

[0114]Hereinafter, a light emitting device according to another embodiment
is described with reference to FIG. 3.

[0115]FIG. 3 is a cross-sectional view showing a light emitting device
according to another embodiment.

[0116]Referring to FIG. 3, in the light emitting device, a pair of
electrodes, including a first electrode 20 and a second electrode 70, are
disposed facing each other on a substrate 10, which may comprise glass,
plastic, or a combination thereof, and a light emitting member 30 is
interposed between the first electrode 20 and the second electrode 70.

[0117]Either the first electrode 20 or the second electrode 70 may be an
anode, and the other electrode may be a cathode.

[0118]The light emitting member 30 includes an emission layer 50 and a
first and a second auxiliary layers 40 and 60, respectively.

[0119]The emission layer 50 may include a light emitting body, which
inherently emits light having one color, such as one of the three primary
colors red, green, and blue. The light emitting device may express white
light by combining the light from the light emitting bodies. The emission
layer 50 includes the light emitting body-polymer composite, which is
further disclosed above, thus further detailed description thereof is
omitted for clarity.

[0120]The first and second auxiliary layers 40 and 60, respectively, are
disposed between the first electrode 20 and the emission layer 50 and
between the emission layer 50 and the second electrode 70, respectively,
and may facilitate charge transport from the first and second electrodes
20 and 70 to the emission layer 50, so as to increase luminous
efficiency. The first and second auxiliary layers 40 and 60 may include
one layer or may comprise at least two layers, and may be omitted if
desired.

[0121]The following examples illustrate the disclosed embodiments in
further detail. However, it is understood that this disclosure is not
limited by these examples.

[0122]Transparent Resin Composition Preparation--1

[0123]A divinyl benzene monomer ("DVB"), a lauryl methacrylate monomer
("LMA"), and a styrene monomer ("ST") are mixed in the amount shown in
Table 1 to provide each cross-linkable composition according to Examples
1 and 2. Furthermore, a cross-linkable composition including only an
acrylate monomer ("Ac") according to Comparative Example 1 is also
prepared.

[0124]Then 0.015 gram (g) of a polymerization initiator of
azobisisobutyronitrile ("AIBN") is added to each cross-linkable
composition. A quantum dot with a core and shell that include InP and
ZnS, respectively, is synthesized and precipitated using ethanol. A 0.1
milliliter (ml) quantity of the precipitate is added to each
cross-linkable composition and the composition uniformly mixed.
Subsequently, the cross-linkable composition including the quantum dot is
measured to determine a concentration using a UV-visible spectrometer and
the concentration of the precipitate is adjusted to provide an optical
density of 0.1.

[0125]The cross-linkable composition is polymerized at a temperature of
80° C. to provide a light emitting body-polymer composite, and
dried at 40° C. under reduced pressure. The dried light emitting
body-polymer composite is pulverized to provide a particulate having a
size of 50 micrometers (μm) or less. A 0.1 g quantity of the obtained
light emitting body-polymer composite and an amine-based hardener are
mixed in 0.2 ml of epoxy resin to provide a transparent resin
composition.

[0127]Each transparent resin composition obtained from Examples 1, 2, and
Comparative Example 1 is coated on a InGaN light emitting diode and
hardened at a temperature of 120° C. for 2 hours to provide a
light emitting device.

[0128]An electric current of 20 mA is applied to the light emitting device
to measure luminance and power conversion efficiency ("PCE") of the light
emitted from the light emitting device. The results are shown in FIG. 4
to FIG. 7.

[0129]FIGS. 4 and 5 are graphs showing changes of luminance and power
conversion efficiency of the light emitting devices according to Examples
1 and 2 over time. More specifically, FIG. 4 is a graph illustrating
lumanance (lumens per watt) versus time (days) of the light emitting
devices according to Examples 1 and 2 over time; and FIG. 5 is a graph
illustrating power conversion efficiency (percent) versus time (days) of
the light emitting devices according to Examples 1 and 2. FIGS. 6 and 7
are graphs showing changes of luminance and power conversion efficiency
of the light emitting device according to Comparative Example 1. More
specifically, FIG. 6 is a graph illustrating lumanance (lumens per watt)
versus time (days) of the light emitting device according to Comparative
Example 1; and FIG. 7 is a graph illustrating power conversion efficiency
(percent) versus time (days) of the light emitting device according to
Comparative Example 1 over time.

[0130]Referring to FIG. 4 and FIG. 6, the light emitting devices
comprising transparent resin compositions according to Examples 1 and 2
have a luminance (e.g. luminous efficacy) of about 10 lumens per watt
(Im/W) or more after about 84 days. On the other hand, the transparent
resin composition according to Comparative Example 1 has significantly
decreased luminance after two days, and the luminance decreased to about
2 Im/W or less after about 20 days. While not wanting to be bound by
theory, it is understood that this result shows that moisture or oxygen
inflow from outside deteriorates the light emitting body.

[0131]Furthermore, referring to FIG. 5 and FIG. 7, it is confirmed that
the light emitting devices using the transparent resin compositions
according to Example 1 and Example 2 maintain a power conversion
efficiency of 10% or more after about 84 days. On the other hand, the
transparent resin composition according to Comparative Example 1 has
remarkably decreased power conversion efficiency after two days, and the
power conversion efficiency decreased to about 1% after about 20 days.
This result shows that the light emitting body is deteriorated due to the
external moisture or oxygen inflow.

[0132]Preparing Resin Composition--2

[0133]A divinylbenzene monomer ("DVB"), a lauryl methacrylate monomer
("LMA"), a styrene monomer ("ST"), and ethylene glycol dimethacrylate
("EGDMA") are mixed in the relative amounts shown in Table 2 to provide
each cross-linkable composition according to Examples 3 to 8 and
Comparative Examples 2 and 3. Then a transparent resin composition is
prepared in accordance with the same procedure disclosed above.

[0134]Each transparent resin composition according to Examples 3 to 8 is
measured to determine a refractive index. The results show that the
transparent resin compositions according to Examples 3 to 8 have
refractive indexes of 1.493, 1.517, 1.541, 1.555, 1.542, and 1.529,
respectively, which corresponds to a range of about 1.4 to about 1.6.

[0136]A light emitting device is fabricated using each transparent resin
composition according to Examples 3 to 8 and Comparative Examples 2 and 4
in accordance with the same procedure disclosed above, and the
characteristics of the light emitting device are analyzed.

[0137]The results are shown in FIG. 8. FIG. 8 is a graph showing the
luminance of the light emitting device (lumens per watt) versus time
(days) according to Examples 3 to 8 and Comparative Examples 2 and 3.

[0138]Referring to FIG. 8, it is confirmed that light emitting devices
using the transparent resin compositions according to Examples 3 to 8
maintain luminance of about 8 Im/W or more after about 60 days. On the
other hand, it is also confirmed that light emitting devices using
transparent resin compositions according to Comparative Example 2 and 3
have very high early luminance, but the luminance remarkably decreases
with the passage of time. While not wanting to be bound by theory, these
results are understood to show that the light emitting body deteriorates
due to inflow of external moisture or oxygen with the passage of time.

[0139]It is also confirmed that the disclosed light emitting device
provides stable transparency and prevents the light emitting body from
deteriorating over time, therefore it is possible to maintain the light
emitting characteristics of the device for a long time.

[0140]While this invention has been described in connection with exemplary
embodiments, it is to be understood that the invention is not limited to
the disclosed embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within the
spirit and scope of the appended claims.